U.S. patent number 6,565,595 [Application Number 09/664,267] was granted by the patent office on 2003-05-20 for two component sleeves.
This patent grant is currently assigned to Scimed Life Systems, Inc.. Invention is credited to Fernando DiCaprio, Joseph M. Lyver.
United States Patent |
6,565,595 |
DiCaprio , et al. |
May 20, 2003 |
Two component sleeves
Abstract
A stent retaining sleeve which may be employed with a stent
delivery system. The sleeves having two tubular components which
are engaged to one another. The first component is an elastomeric
tube which is designed to be disposed about the end of a stent and
the portion of the catheter immediately adjacent thereto. The first
component includes an inner surface which may be at least partially
prelubricated with a lubricant. The second sleeve component is a
second elastomeric tube which partially overlaps at least a portion
of the first tube and is engaged thereto. A second portion of the
second tube is constructed and arranged to engage a portion of the
catheter shaft immediately adjacent thereto.
Inventors: |
DiCaprio; Fernando (Mendota
Heights, MN), Lyver; Joseph M. (Hopkins, MN) |
Assignee: |
Scimed Life Systems, Inc.
(Maple Grove, MN)
|
Family
ID: |
24665309 |
Appl.
No.: |
09/664,267 |
Filed: |
September 18, 2000 |
Current U.S.
Class: |
623/1.11 |
Current CPC
Class: |
A61F
2/958 (20130101); A61F 2002/9583 (20130101) |
Current International
Class: |
A61F
2/06 (20060101); A61F 002/06 () |
Field of
Search: |
;606/1,108,194,195,198
;623/1.1,1.11,12,1.12 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Other References
US. patent application Ser. No. 09/664,268, ScottHanson, filed on
Sep. 18, 2000. .
U.S. patent application Ser. No. 09/427,805, L. Wang, filed on Oct.
27, 1999..
|
Primary Examiner: Thaler; Michael H.
Attorney, Agent or Firm: Vidas, Arrett & Steinkraus,
P.A.
Claims
What is claimed is:
1. A stent delivery system comprising: a catheter, the catheter
having a stent mounting region and a catheter shaft; a stent, the
stent disposed about the stent mounting region, the stent
characterized as having two ends; and at least one stent retaining
sleeve, the at least one stent retaining sleeve having: a fist
tubular member, the first tubular member having a length, the first
tubular member having a first portion and a second portion and an
inside surface and an outside surface, at least a portion of the
inside surface of the first portion of the first tubular member
engagingly disposed about at least one end of the stent, the inside
surface of the second portion of the first tubular member disposed
about a portion of the catheter; and a second tubular member, the
second tubular member having a length, the second tubular member
having a first portion, a first portion end defined by the
termination of the first portion, a second portion, a second
portion end defined by the termination of the second portion, an
inside surface and an outside surface, the inside surface of the
first portion of the second tubular member overlapping the outside
surface of at least the second portion of the first tubular member,
the inside surface of the first portion of the second tubular
member and the outside surface of the at least the second portion
of the first tubular member being engaged to one another, wherein
the first portion of the first tubular member extends from the
first portion end of the second tubular member, the inside surface
of the second portion of the second tubular member engagingly
disposed about a portion of the catheter shaft, wherein less than
half of the length of the first tubular member overlaps with the
second tubular member.
2. A stent delivery system of 1, wherein the at least a portion of
the inside surface of the first tubular member further comprises a
lubricious surface.
3. The stent delivery system of claim 2, wherein the lubricious
coating is at least partially composed of at least one member of
the group consisting of one or more silicones, PVP, PPO,
polyethylene oxide and neopentyl glycol diacrylate polymerized in a
solution of water and isopropyl alcohol in the presence of a
photoinitiator, oil, wax, and any combination thereof.
4. The stent delivery system of claim 2, the lubricious surface
comprising a plasma enhanced surface, the plasma enhanced surface
being produced by exposing the at least a portion of the inside
surface of the first tubular member to a charged ion field, the
charged ion field modifying the at least a portion of the inside
surface of the first tubular member, thereby producing a modified
surface having enhanced lubricity.
5. The stent delivery system of claim 4, wherein the modified
surface is cross-linked.
6. The stent delivery system of claim 1, wherein the first tubular
member is at least partially composed of an elastomeric
polymer.
7. The stent delivery system of claim 1, wherein the first tubular
member is at least partially composed of polyurethane.
8. The stent delivery system of claim 1, wherein the first tubular
member is at least partially constructed from biocompatible medical
grade aromatic polyurethane.
9. The stent delivery system of claim 1, wherein the second tubular
member is composed at least partially of at least one member of the
group consisting of: polyurethane, polycarbonate-polyurethane
co-polymer, polyurethane-polycarbonate blends, and any combination
thereof.
10. The stent delivery system of claim 1, wherein the second
tubular member is composed of a combination of polyurethane and at
least one polyurethane-polycarbonate blend.
11. The stent delivery system of claim 1, wherein the second
tubular member is composed of a combination of first
polycarbonate-polyurethane co-polymer and a second
polycarbonate-polyurethane co-polymer.
12. The stent delivery system of claim 11, wherein the combination
further comprises substantially 50 percent of the first
polycarbonate-polyurethane co-polymer and substantially 50 percent
of the second polycarbonate-polyurethane co-polymer.
13. The stent delivery system of claim 1, wherein at least a
portion of the inside surface of the first portion of the second
tubular member is fixedly engaged to at least a portion of the
outside surface of at least the second portion of the first tubular
member.
14. The stent delivery system of claim 13, wherein the at least a
portion of the inside surface of the first portion of the second
tubular member is heat welded to the at least a portion of the
outside surface of at least the second portion of the first tubular
member.
15. The stent delivery system of claim 13, wherein the at least a
portion of the inside surface of the first portion of the second
tubular member is laser welded to the at least a portion of the
outside surface of at least the second portion of the first tubular
member.
16. The stent delivery system of claim 13, wherein the at least a
portion of the inside surface of the first portion of the second
tubular member is chemically bonded to the at least a portion of
the outside surface of at least the second portion of the first
tubular member.
17. The stent delivery system of claim 13, wherein the at least a
portion of the inside surface of the first portion of the second
tubular member is physically bonded to the at least a portion of
the outside surface of at least the second portion of the first
tubular member.
18. The stent delivery system of claim 13, wherein the at least a
portion of the inside surface of the first portion of the second
tubular member overlaps in an interference fit the at least a
portion of the outside surface of at least the second portion of
the first tubular member.
19. The stent delivery system of claim 1, wherein at least a
portion of the inside surface of the second portion of the second
tubular member is frictionally engaged to at least a portion of the
catheter shaft.
20. The stent delivery system of claim 1, wherein the inner surface
of the second portion of the second tubular member is fixedly
engaged to at least a portion of the catheter shaft.
21. The stent delivery system of claim 1, wherein the inner surface
of the second portion of the second tubular member is heat welded
to at least a portion of the catheter shaft.
22. The stent delivery system of claim 1 wherein the inner surface
of the second portion of the second tubular member is laser welded
to at least a portion of the catheter shaft.
23. The stent delivery system of claim 1, wherein the inner surface
of the second portion of the second tubular member is chemically
bonded to at least a portion of the catheter shaft.
24. The stent delivery of claim 1, wherein the inner surface of the
second portion of the second tubular member is physically bonded to
at least a portion of the catheter shaft.
25. The stent delivery system of claim 1, wherein the first tubular
member is elastic.
26. The stent delivery system of claim 25, wherein the first
tubular member is made from a material comprising polyurethane.
27. A stent delivery system comprising: a catheter, the catheter
having a stent mounting region and a catheter shaft; a stent, the
stent disposed about the stent mounting region, the stent
characterized as having two ends; at least one stent retaining
sleeve, the at least one stent retaining sleeve having: a first
tubular member, the first tubular member having a length, a first
portion and a second portion and an inside surface and an outside
surface, at least a portion of the inside surface of the first
tubular member having a lubricious coating thereon, the inside
surface of the first portion of the first tubular member engagingly
disposed about at least one end of the stent, the inside surface of
the second portion of the first tubular member disposed about a
portion of the catheter; a second tubular member, the second
tubular member having a length, a first portion, a first portion
end defined by the termination of the first portion and a second
portion, a second portion end defined by the termination of the
second portion, and an inside surface and an outside surface, the
inside surface of the first portion of the second tubular member
overlapping the outside surface of at least the second portion of
the first tubular member, the inside surface of the first portion
of the second tubular member and the outside surface of the at
least the second portion of the first tubular member being engaged
to one another, wherein the first portion of the first tubular
member extends from the first portion end of the second tubular
member and less than half of the length of the first tubular member
overlaps with the second tubular member, the second portion at
least partially folded over on to itself whereby the outer surface
of the second portion of the second tubular member is engagingly
disposed about at least a portion of the catheter shaft.
28. The stent retaining sleeve of claim 27, wherein the first
tubular member is elastic.
29. The stent retaining sleeve of claim 28, wherein the first
tubular member is made from a material comprising polyurethane.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
Not Applicable
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
Not Applicable
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a medical device delivery systems. More
particularly the present invention is directed to stent delivery
systems which employ stent retaining socks or sleeves which aid in
retaining the stent to the catheter prior to delivery of the stent
into a body vessel. The present invention provides for stent end
retaining sleeves, wherein each sleeve has two components which are
engaged to one another. In at least one embodiment of the invention
the sleeve or sleeves are composed of a first tubular portion of
material such as polyurethane, the material may be lubricious or
have alubricious coating thereupon. The sleeve may also have a
second tubular portion composed of a polyurethane-polycarbonate
blend such as a mixture of Carbothane.TM. and Chronoflex.TM.. The
second tube has a first end which at least partially overlaps and
is engaged to a portion of the first tube. In at least one
embodiment of the invention first end of the second tube and at
least a portion of the first tube are connected together. A second
portion of the second tube is designed to engage a portion of a
catheter shaft, while a portion of the first tube is constructed
and arranged to be disposed about a stent prior to stent delivery.
Other inventive aspects and embodiments of the present end
retaining sleeves will be made apparent below.
2. Description of the Related Art
Stents and stent delivery assemblies are utilized in a number of
medical procedures and situations and as such their structure and
function are well known. A stent is a generally cylindrical
prosthesis introduced via a catheter into a lumen of a body vessel
in a configuration having a generally reduced diameter and then
expanded to the diameter of the vessel. In its expanded
configuration, the stent supports and reinforces the vessel walls
while maintaining the vessel in an open, unobstructed
condition.
Both self-expanding and inflation expandable stents are well known
and widely available in a variety of designs and configurations.
Self-expanding stents must be maintained under positive external
pressure in order to maintain their reduced diameter configuration
during delivery of the stent to its deployment site. Inflation
expandable stents may be crimped to their reduced diameter about
the delivery catheter, maneuvered to the deployment site, and
expanded to the vessel diameter by fluid inflation of a balloon
positioned on the delivery catheter. The present invention is
particularly concerned with delivery and deployment of inflation
expandable stents, although it is generally applicable to
self-expanding stents when used with balloon catheters.
Inflation expandable stent delivery and deployment assemblies are
known which utilize restraining means that overlie the stent during
delivery. U.S. Pat. No. 4,950,227 to Savin et al, relates to an
expandable stent delivery system in which a sleeve overlaps the
distal or proximal margin (or both) of the stent during delivery.
That patent discloses a stent delivery system in which a catheter
carries, on its distal end portion, a stent which is held in place
around the catheter prior to and during percutaneous delivery by
means of one and preferably two sleeves. The sleeves are positioned
around the catheter with one end portion attached thereto and
overlap an end portion(s) of the stent toehold it in place on the
catheter in a contracted condition. Each sleeve is elastomeric in
nature so as to stretch and release the stent when it expands for
implantation. The stent is expandable by means of the expandable
balloon on the catheter. During expansion of the stent at the
deployment site, the stent margins are freed of the protective
sleeve(s). As indicated above, the present invention is
particularly directed to stent retaining sleeves having at least
two components. In addition to the above, other types of stent
delivery sleeves are known.
In some stent delivery devices, a lubricant is applied to the
inside surface of the sleeve or the sleeve itself is made to be
particularly lubricious. A problem with providing such lubricity is
that the lubrication tends to be applied to the entire sleeve,
including the portion of the sleeve which is to be affixed to the
catheter shaft. The presence of lubrication on the portion of the
sleeve which is to be affixed may make it difficult to engage the
sleeve to the catheter. In some alternative sleeve arrangements one
or more lubricants are added after the sleeve is mounted onto the
catheter, but such after-the-fact lubrication is often difficult to
apply and may result in uneven lubrication of the sleeve.
The present invention addresses these and other problems associated
with many prior sleeve designs by providing each sleeve with two
portions, a first portion which is intended to overlie the ends of
a stent and which may have an internal surface, which in-whole or
in-part, is inherently lubricious or has a lubricant applied
thereto, and a second portion which at least partially overlies the
first portion and which has an internal surface which may be
readily engaged to the catheter shaft as well as the outer surface
of the first portion of the sleeve. The overlap between the first
portion and second portion also provides the sleeve with a buckle
or break point which enhances the capacity of the first portion of
the sleeve to retract off of the sleeve as described in detail
below. The two portions may be connected to one another by an
interference fit, bonding, or welding, such as laser welding.
The entire content of all patents and applications listed within
the present patent application are incorporated herein by
reference.
BRIEF SUMMARY OF THE INVENTION
This invention provides for a stent retaining sleeve or sleeves
which may be employed with a stent delivery system. The inventive
sleeves have two components which are engaged to one another. The
first component is an elastomeric tube which is designed to be
disposed about the end of a stent and the portion of the catheter
immediately adjacent thereto. The first component is a tubular
portion of sleeve material which includes an inner surface as well
as an outer surface both of which may be at least partially
lubricated. The second sleeve component is a second tube of sleeve
material which is preferably constructed of a different material
than the first tube material. In at least one embodiment of the
invention the material of the second component has a greater
durometer Shore D hardness than that of the first component. A
first portion of the.second component overlaps at least a portion
of the first component and is engaged thereto. A second portion of
the second, component is constructed and arranged to engage a
portion of the catheter shaft immediately adjacent thereto. In at
least one embodiment of the invention the sleeve may be mounted
singly or in pairs about the end or ends, respectively, of a stent
on a stent delivery catheter. Where the sleeve or sleeves are
utilized in a stent delivery system, the sleeve or sleeves are
constructed and arranged to readily retract off of the end or ends
of the stent when the stent exerts an outwardly acting radial force
on the portion of the sleeve(s) overlying the stent.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
A detailed description of the invention is hereafter described with
specific reference being made to the drawings in which:
FIG. 1 is a side view of an embodiment of the invention;
FIG. 2 is a side view of an embodiment of the invention;
FIG. 3 is a side view of an embodiment of the invention;
FIG. 4 is a side view of an embodiment of the invention;
FIG. 5 is a side view of an embodiment of the invention;
FIG. 6 is a side view of the embodiment shown in FIG. 3 in a
potential post stent delivery state;
FIG. 7 is a side view of the embodiment shown in FIG. 3 in a
potential post stent delivery state;
FIG. 8 is a side view of an embodiment of the invention; and
FIG. 9 is a side view of the embodiment of the invention shown in
FIG. 8 in a potential post stent delivery state.
DETAILED DESCRIPTION OF THE INVENTION
In a basic embodiment, the present invention is directed to one or
more stent retaining socks or sleeves such as the pair of sleeves,
indicated generally at 10, shown in FIG. 1. The sleeves 10, may be
employed on a stent delivery catheter, indicated generally at 50,
such as is shown in FIGS. 3-9. Each of the various sleeves 10, are
made up of a first tubular member 12 and a second tubular member
22. The first tubular member has an inside surface 14 and an
outside surface 16, as well as a first section 18 and a second
section 20.
In the embodiment shown in the various figures the first tubular
member 12 may be made of one or more thermoplastic elastomers i.e.
block copolymers; copolymers and terpolymers of ethylene;
homopolymers, copolymers and terpolymers of propylene; ethylene
a-olefins; polyesters; polyamides; polyurethanes, such as
TECOTHANE.TM. a biocompatable medical grade aromic polyurethane
available from Thermedics, Inc.; polycarbonates, vinyl copolymers;
ionomer materials and so forth. More specifically, materials such
as nylon, SELAR.TM., polyether-polyester block copolymers (i.e.
HYTRBL.TM. from DuPont or ARNITEL.TM. from DSM, Netherlands),
PEBAX.TM.(polyether block amide copolymers), SURLYN.TM.,
polyethylene terephthalate, pblytetrafluoroethylene, polyvinyl
chloride, polyetherurethanes, polyesterurethanes, polyurethane
ureas, polyurethane siloxane block copolymers, silicone
polycarbonate copolymers, ethylene vinyl acetate copolymers,
acrylonitrile-butadiene-styrene copolymers; polyphenylene sulfides;
copolyesters or other similar extrudable thermoplastic, polymeric
materials, and/or composites thereof may be utilized in the present
invention.
The second tubular member 22, may be manufactured from a
polyurethane, a polycarbonate-polyurethane co-polymer, one or more
polyurethane-polycarbonate blends, or any combination thereof.
In the embodiment shown in FIGS. 1 the first tubular member 12 is
made from TECOTHANE.TM., the second tubular member 22 is composed
of a mixture of commercially available polycarbonate-polyurethane
co-polymers CARBOTHANE.TM. from Thermedics, Inc. and CHRONOFLEX.TM.
from CT Biomaterials. The precise combination of
polycarbonate-polyurethane co-polymers in the second tubular member
22 may vary, but in the present embodiment the second tubular
member 22 is composed of a 50/50 mixture of CARBOTHANE.TM. and
CHRONOFLEX.TM.. The second tubular member 22 may act to provide the
sleeve 10 with a more rigid structure than the first tubular member
12 would alone.
The second tubular member 22 may also be provided with a greater
hardness or durometer than the first tubular member 12. In the
embodiments shown, the first tubular member 12 has a Shore D
hardness no greater than 1055D as measured by the Shore D hardness
scale; the second tubular member 22 has a Shore D hardness equal to
or greater than that of the first tubular member 12. By providing
the members 12 and 22 with various hardnesses, the sleeve 10 may be
configured to provide a wide range of retraction
characteristics.
The first tubular member 12 may be provide with a portion which is
lubricious or may be coated with one or more lubricant or
lubricants 24. The lubricant or lubricants may be hydrophobic
and/or hydrophilic, and may be selected from, but are not limited
to, one or more of the following substances: silicones; PVP
(polyvinyl pyrrolidone); PPO (polypropylene oxide); PEO;
BioSlide.TM. coating produced by SciMed (BioSlide.TM. is a
hydrophilic lubricious coating comprising polyethylene oxide and
neopentyl glycol diacrylate polymerized in a solution of water and
isopropyl alcohol in the presence of a photoinitiator such as
azobisisobutronitrile); oils, such as mineral oil, olive oil,
vegetable oil, or other natural oils, and wax. Lubricant 24 may be
applied to the inside surface 14 of the first tubular member 12 or
any portion thereof Lubricant may also be applied to at least a
portion of the first section 18 on the outside surface 16 as may be
desired. Alternatively, in the embodiment shown in FIG. 1 the
inside surface 14 may be plasma treated through exposure to a
charged ion field to promote cross-linking, the resulting modified
cross-linked surface having improved lubricious qualities which may
alleviate any need for an extra lubricant such as previously
described.
Additionally, the respective compositions of the first and second
tubular members 12 and 22 are such that the materials may be bonded
together. In the various embodiments shown in FIGS. 1-9 the outside
surface 16 of the second portion 20 of the first tubular member 12
is engaged to the inside surface 26 of the first portion 30 of the
second tubular member 22. The engagement may be by interference
fit, chemical or physical bonding, or welding such as heat or laser
welding, or any combination thereof. In the embodiment shown in
FIG. 1 it may be seen that the portions 20 and 30 are laser welded
together with a lap weld 34. The types or methods of engagement
described above between portions 20 and 30 may also be utilized .to
attach at least a part of the inside surface 26 of the second
portion 32 of the second tubular member 28 to the shaft 52 of a
balloon catheter 50 such as may be seen in FIGS. 3-5. Specifically,
in FIG. 3 the inside surface 26 of section 32 is laser welded to
the catheter shaft 52, however any of the previously mentioned
engagement methods could be used to secure the sleeve 10 to the
catheter shaft 52.
While, in FIG. 3 the inside surface 26 of section 32 of the second
tubular member 22 is laser welded to the catheter shaft 52. A
portion of the inside surface 14 of section 18 of the first tubular
member 12 overlies each end of a stent 54 prior to stent delivery.
As previously described, the inside surface 14 of the first tubular
member may have a lubricant 24 applied thereto. The lubricant 24
may be applied to the entire inside surface 14 such as is seen in
FIG. 5. Alternatively, the lubricant 24 may be selectively applied
to only a portion of the sleeve, such as the portion of the sleeve
18 which overlies the stent 54, such as is shown in FIG. 4. As
previously mentioned, the portion of the sleeve 18 which may
overlay the stent 54, may be modified to have improved lubricity by
treating at least a portion of the inside surface 14 prior to
placement of the sleeves 10 on the stent delivery catheter 50. An
example of such treatment would be to expose only portion 18 of the
inside surface 14 to a plasma field as previously discussed.
Retraction of the sleeves 10 may occur in a variety of manners. For
instance, in the embodiment shown in FIG. 6 the sleeves are
constructed and arranged to retract off of only the ends of the
stent 54, when the balloon 62 is inflated. In the embodiment shown
in FIG. 6, the expansion of the balloon 62 combined with the
elastic nature of the first tubular member 12 allows the sleeve to
retract to an extent sufficient to allow the stent 54 to be
released.
In an alternative embodiment shown in FIG. 7, the sleeves 10 are
designed so that during stent delivery the sleeves will slide or
roll off of the stent 54 as well as balloon cones 60. In the
embodiment shown, the thickened portion 66 of the sleeve 10 (which
results from the overlap of the first tubular member 12 and the
second tubular member 22) acts as a breaking or folding point for
the sleeve 10 whereupon portion 18 of the first tubular member 12
will tend to fold over and at least partially overlie during and
subsequent to stent delivery. As may be seen, the thickened portion
66 may assist the retracted sleeve 10 into taking on an S-shaped
retraction configuration. Such a configuration helps to ensure that
the sleeve 10 is fully retracted off of the stent 54 and balloon
60.
An additional type of sleeve retraction is shown in FIG. 9 and is
best accomplished by an alternative embodiment of the invention
shown in FIG. 8, wherein a portion of the outside surface 28 of the
second section 32 of the second tubular member 22 is engaged to the
catheter shaft 52. In such an embodiment the second tubular member
22 is actually folded over on to itself where it is engaged to the
catheter shaft 52. Such a folded over engagement may employ any of
the engagement methods previously discussed. The folded over
configuration shown in FIG. 8 provides the sleeve with a second
breaking point 67 which provides a tension which assists in pulling
the sleeve 19 completely off of stent 54 as well as the balloon
cones 60 when the stent 54 is expanded.
In the various embodiments shown in FIGS. 3-9, the portion of the
sleeve 26 which is in contact with the catheter shaft 52 may be at
least partially affixed to the catheter shaft 52. In this
embodiment one or both of the tubular members 12 and 22 may be
configured to provide a "snapping" action so that the sleeve 10 is
actively pulled off of the stent 54 in an elastic manner thereby
providing an even greater tendency for the sleeves 10 to full
retract off of the stent 54.
In addition to being directed to the embodiments described above
and claimed below, the present invention is further directed to
embodiments having different combinations of the features described
above and claimed below. As such, the invention is also directed to
other embodiments having any other possible, combination of the
dependent features claimed below.
The above examples and disclosure are intended to be illustrative
and not exhaustive. These examples and description will suggest
many variations and alternatives to one of ordinary skill in this
art. All these alternatives and variations are intended to be
included within the scope of the attached claims. Those familiar
with the art may recognize other equivalents to the specific
embodiments described herein which equivalents are also intended to
be encompassed by the claims attached hereto.
* * * * *